Certified for SIL2/PLd, Category 3 applications, Leine & Linde 850 Shaft and 862 Hollow-shaft Encoders allow incremental encoders to be applied where safe operation of machinery is necessary without requiring redundant encoder or secondary sensing device. Output signal validity is assured by comparing raw sensor signals to digital output states and validating that against actual values output to control. If values are not in agreement, status signal signifies output is invalid.